What information is required to calculate the average atomic mass of an element?

All isotopes of the element their atomic masses in their relative abundance

answer

the ions in solute supperate from eachouthere

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer